The last time a Democratic presidential candidate won Arizona was 16 years ago, when Bill Clinton carried it in 1996.

The time before that? More than half a century ago, when Harry Truman won the state.

But as Republicans compete in their own primary there today, President Barack Obama's re-election team also has its eye on Arizona, a state where a growing Hispanic electorate and a deep divide on immigration policy could potentially help the president collect a much-needed 11 electoral votes in November.

A win there would be a reach, however. A recent NBC/Marist poll put Obama's approval rating in the state below 40%, and it showed him trailing most of the Republican presidential candidates there.

While Obama -- who didn't contest Arizona four years ago -- lost it by eight percentage points in 2008, his team believes that Sen. John McCain's less-than-double-digit victory in his own home state did much to lay bare Republicans' vulnerability there.

And, four years later, Obama's opponent is likely to face a much harsher reception from the state's growing Latino electorate than McCain, whose push for comprehensive immigration reform nearly derailed his candidacy early in the GOP primary.

From vows to veto the DREAM Act to heavy courtship of controversial endorsers like Arizona's Maricopa County Sheriff Joe Arpaio, GOP candidates' language on immigration has prompted public worry from Republican Hispanic groups as well as from party leaders like former Gov. Jeb Bush.

In Arizona, which became ground zero for the immigration debate after its 2010 passage of legislation that would give police broad authority to detain suspected illegal residents, Democrats have a favorite noun to describe Republican rhetoric on the matter.

Those working to turn the state blue were thrilled to hear Mitt Romney call Arizona's stringent SB 1070 immigration measure "a model" for the nation's policies during a Feb. 22 debate in Mesa. They believe that kind of language -- underscored by Romney's endorsement on Sunday by Gov. Jan Brewer, who signed the bill into law -- could further mobilize Arizona voters looking for more moderate solutions to the immigration issue.

Harnessing that feeling on the ground will be the task of the campaign's substantial Arizona field operation.

The re-election campaign has three field offices already in Arizona -- in Phoenix, Tucson and Flagstaff -- and another set to open in heavily Hispanic Glendale in the coming weeks. The campaign says that staff and volunteers have held almost 500 voter registration sessions and more than 200 phone banks since the spring. Much of that effort is focused on the Hispanic community, with events held at Hispanic supermarkets and weekly Spanish- and English-language phone banks targeting Latinos. The campaign recently hired a Mexican-American regional field director.

While Team Obama hasn't yet invested in paid media there, the DNC has aired TV advertisements, including a six-day anti-Romney buy last year.

With the number of voting age Hispanic citizens growing by a whopping 85% last decade, per Census data, the benefits of such a focus are obvious. But the lift may still prove to be a heavy one.

The NBC/Marist Arizona survey this month also found that 51% of Hispanics approve of the president's performance, with 34% disapproving and 15% unsure.

Compare that to the 2008 numbers: Obama won 56% of the Latino vote in Arizona compared to McCain's 41%.

Luis Heredia, the executive director of the Arizona Democratic Party, estimates that Obama would have to boost that number to at least 65% in November to get over the finish line.

And Dill, who served as deputy state director for the Clinton/Gore win in 1996, puts that number even higher, at 68%.

He added that Democrats must be careful in 2012 to tailor their message to a diverse Hispanic community, saying that the party stumbled in past elections by treating the group as a single monolithic block.

"A big part of it had been our fault as campaign managers, as leaders," Dill said. "We had sort of homogenized the Hispanic community in Arizona into one group. And they're not, they're very diverse."

This year, Democrats say there's plenty of reasons to be optimistic.

Obama's team points to Democrats' double-digit mayoral victories in Tucson and Phoenix last year as well as the recall of Arizona State Senate president and author of SB 1070.

And Heredia adds that downballot races, like the one to replace retiring Rep. Gabby Giffords, will help build excitement for activists locally.